Damping cable vibration for a cable-stayed bridge using adjustable fluid dampers

Passive fluid damper is one of most widely used control devices for damping vibration of stay cables in a cable-stayed bridge in practice. However, each stay cable features unique dynamic characteristics and requires a specific damper to achieve the best control performance, which engenders many troubles in manufacture, implementation and maintenance of dampers. This paper presents a new approach for damping vibration of stay cables in a cable-stayed bridge by using adjustable fluid dampers. The principle and main features of adjustable fluid dampers with shape memory alloy (SMA) actuators are first introduced. The solution of a taut cable with the adjustable fluid damper described by the Maxwell model is provided. A most favorable design principle is then proposed for selecting the least types of adjustable fluid dampers for damping vibration of a few hundreds stay cables in a cable-stayed bridge. A case study of stay cables in a super long span cable-stayed bridge is finally performed, demonstrating that only two types of adjustable fluid dampers are required for damping vibration of all stay cables in the bridge. (c) 2007 Elsevier Ltd. All rights reserved.